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How to reduce the ratio mao/metallocene
Author(s) -
Kaminsky W.
Publication year - 1995
Publication title -
macromolecular symposia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.257
H-Index - 76
eISSN - 1521-3900
pISSN - 1022-1360
DOI - 10.1002/masy.19950970108
Subject(s) - metallocene , bimetallic strip , cyclopentadienyl complex , materials science , polymer , post metallocene catalyst , polymer chemistry , catalysis , chemistry , organic chemistry , polymerization , composite material
The optimal ratio of Al/Zr in Metallocene/Methylalumoxane catalysts lies between 5000 to 10000. Bimetallic deactivation reactions and equilibria are responsible for this high excess. Substitution at the cyclopentadienyl or indenyl ligands can decrease the possibility for a hydrogen transfer and deactivation resulting in higher activity, higher molecular weights of the polymers and less excess of MAO. The MAO/metallocene ratio can also be reduced by supporting the metallocene on silica.